1. Field of the Invention
This invention describes a 3D x-ray imaging system using the methods of image reconstruction for applications in security screening of baggage or cargo, and medical imaging.
2. Description of the Related Art
2D x-ray imaging is widely used both in the areas of medicine, and security screening of baggage and cargo. 2D imaging has its limitations and therefore Computed Axial Tomographic (CAT) or simply Computed Tomographic (CT) systems are used in the field of medicine and also for screening of baggage to detect for explosives, objects of threat and contraband.
While CT systems have been employed usefully in the field of medicine, they expose the patient to x-ray dose which is 100 times or more than that of an ordinary x-ray image. Further, these systems are very costly, in the vicinity of a million dollars or more. In the field of security screening, the CT systems are effective in checking for explosives, but are very expensive, slow, large, and cannot be made large enough to screen larger air cargo or shipping containers.
CAT systems employ a complex rotating gantry which makes the system costly, large, and power hungry. In order to do away with the rotating gantry, there has been effort to generate 3D images using the methods which are referred to as Tomosynthesis or Tomography. Such methods use only a few views or projections compared to a few hundreds used by CAT systems. However, these methods are still in the research and design phase.
Accordingly, the objects of this invention are to overcome the above limitations as stated next.